Obscuring an accelerometer signal

ABSTRACT

The present disclosure presents techniques for determining when to obscure an accelerometer signal from an accelerometer of a mobile device. The techniques include determining whether a user has been prompted to provide sensitive input data to the mobile device using an input device of the mobile device. When the user has been prompted to provide sensitive input data, the technique includes obscuring a portion of an accelerometer signal outputted from an accelerometer, and receiving the sensitive input data from the user at the input device while the accelerometer signal is obscured. In some embodiments, the accelerometer signal can be obscured by (i) switching the accelerometer  216  off, (ii) inserting a random noise signal into the accelerometer signal, (iii) masking the low-order bits of the accelerometer signal, (iv) passing the accelerometer signal through a filter, (v) actuating a vibrator of the mobile device, and/or (vi) otherwise degrading the accelerometer signal.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/281,766 filed on Oct. 26, 2011. The entire disclosure of the aboveapplication is incorporated herein by reference.

FIELD

The present disclosure is directed to techniques for obscuring anaccelerometer signal in a mobile device.

BACKGROUND

The background description provided herein is for the purpose ofgenerally presenting the context of the disclosure. Work of thepresently named inventors, to the extent it is described in thisbackground section, as well as aspects of the description that may nototherwise qualify as prior art at the time of filing, are neitherexpressly nor impliedly admitted as prior art against the presentdisclosure.

A “mobile device” generally refers to a computing device having userinterface, a display, and a processor. For example, the mobile devicemay be a mobile phone, tablet computing device, global positioningsystem transceiver, and the like. Mobile devices may selectively connectto a network such as the Internet and/or a mobile telephone network. Auser may input information, e.g., text, to the mobile device via a userinterface (or “character layout”) such as a keyboard and/or a numberpad. Due to size constraints, however, mobile devices may include apartial QWERTY-based physical keyboard. Additionally or alternatively,mobile devices may include touch displays, e.g., capacitive sensingdisplays, which both display information to the user and receive inputfrom the user. For example, these mobile devices may display a characterlayout to the user similar to the partial QWERTY-based keyboard ornumber pad.

Mobile devices are increasingly being used to store and access sensitiveuser data. For example, users may store passwords and/or account numberson their mobile devices. In another example, users may use their mobiledevices to access healthcare records, bank accounts, internal corporateemails, and other highly private records. It is not a secret that thereare malicious interlopers who wish to obtain sensitive user data byaccessing these mobile devices, or to intercept the sensitive user dataas it is being transmitted over a network. These interlopers use varioustechniques to obtain the sensitive user data stored in the mobiledevice. One such technique that an interloper may implement is tomonitor an accelerometer signal outputted by an accelerometer of themobile device to determine a location at which user input was provided.

SUMMARY

According to various embodiments of the disclosure, acomputer-implemented technique is disclosed. The technique can includedetermining, at a mobile device, whether a user has been prompted toprovide sensitive input data to the mobile device using an input deviceof the mobile device. When the user has been prompted to providesensitive input data to the mobile device, the technique can includeobscuring a portion of an accelerometer signal output from anaccelerometer of the mobile device, and receiving the sensitive inputdata from the user while the portion of the accelerometer signal isobscured.

According to various embodiments of the disclosure, a mobile device isdisclosed. The mobile device can include an input device having aphysical interface configured to receive input data from a user, anaccelerometer module that outputs an accelerometer signal and aprocessor in communication with the input device and the accelerometermodule. The processor can be configured to: determine whether the userhas been prompted to provide sensitive input data to the mobile deviceusing the input device, and when the user has been prompted to providethe sensitive input data to the mobile device, to effect obscuring of aportion of an accelerometer signal for a period during which the user isproviding the sensitive input data.

Further areas of applicability of the present disclosure will becomeapparent from the detailed description provided hereinafter. It shouldbe understood that the detailed description and specific examples areintended for purposes of illustration only and are not intended to limitthe scope of the disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure will become more fully understood from thedetailed description and the accompanying drawings, wherein:

FIG. 1 illustrates an example of a user interacting with a mobile deviceaccording to some implementations of the present disclosure;

FIG. 2 is a functional block diagram of the mobile device of FIG. 1according to some implementations of the present disclosure;

FIG. 3 is a flow chart illustrating an example technique for obscuringan accelerometer signal according to some implementations of the presentdisclosure;

FIGS. 4 through 7 are functional block diagrams of a processor and anaccelerometer module of a mobile device according to someimplementations of the present disclosure; and

FIG. 8 is a functional block diagram of a processor, a vibrator, and anaccelerometer module of a mobile device according to someimplementations of the present disclosure.

DETAILED DESCRIPTION

Referring now to FIG. 1, an example of a mobile device 100 is shown. Themobile device 100 may be a mobile phone, a tablet computer, or the like.The mobile device 100 generally includes a display 104. For example, thedisplay 104 may be a touch display, such as a capacitive sensingdisplay. The mobile device 100 may additionally or alternatively includea physical character layout, e.g., a partial QWERTY-based keyboard 116or a number layout (not shown). The touch display 104 may displayinformation to a user and receive input from the user. For example, theuser may input information to the mobile device 100 via the touchdisplay 104 using one or more fingers 112.

Referring now to FIG. 2, the mobile device 100 of FIG. 1 can include aprocessor 210, an input device 212, and an accelerometer module 214which includes an accelerometer 216. It is appreciated that theforegoing set of components is non-exhaustive and not intended to belimiting. For example the mobile device 100 may include a microphone, anaudio output device, and/or one or more antennas for communicating with,for example, a Wi-Fi base station, a cell tower, or another device.

The processor 210 can be configured to execute one or more applications.For instance, the processor 210 can execute an operating system 220. Theoperating system 220 may execute a plurality of other applications,including, for example only, an authentication application 222, one ormore third party applications 224, a web browser application 226, and aGlobal Positioning System (GPS) application 228. It is appreciated thatthe foregoing list is provided for explanation purposes only. Further,while the mobile device 100 is illustrated as having one processor 210,it should be appreciated that multiple processors can execute theoperating system and/or the other applications.

The input device 212 provides an interface for a user to interact withthe mobile device 100. For instance, the input device 212 may include atouch display 104 that displays a QWERTY keyboard or a number pad,and/or a QWERTY-based keyboard. The user utilizes the input device 212to provide input data to the mobile device 100. The input data iscommunicated from the input device 212 to the processor 210.

As described above, the accelerometer module 214 may include anaccelerometer 216. An accelerometer 216 is a device that can detectmovement of the mobile device 100. The accelerometer 216 can output anaccelerometer signal based on the movement, which can then be providedto the processor 210. It will be appreciated that the accelerometer 216may be a digital accelerometer that outputs a digital accelerometersignal or an analog accelerometer that outputs an analog accelerometersignal. As will be discussed below, the accelerometer signal can be usedby many different applications to provide information relating to themovement of the device.

When a user is using the input device 212 to enter sensitive input data,e.g., a password or login-gesture, an interloper can monitor theaccelerometer signal to determine the letters or numbers that the userhas entered. In the frequency domain of the accelerometer signal, thelower frequencies can provide information regarding the movements of themobile device 100 about one or more axes. In some scenarios, theinterloper can monitor a specific frequency or frequency range, e.g.,lower frequencies, of the accelerometer signal to determine locations onthe device that the user has pressed.

As discussed, the processor 210 can execute the one or moreapplications. For example, the processor 210 can execute the operatingsystem 220 of the mobile device 100. The processor 210 may furtherexecute, via the operating system 220, other applications, such as theauthentication application 222, the third party application 224, the webbrowser application 226, and the GPS application 228.

The authentication application 222 may be an application forauthenticating a user of the mobile device 100. The authenticationapplication 222 can display a screen requesting that a user providesensitive input data, e.g., a password or a predetermined gesture, toperform authentication of the user and provide access to the mobiledevice 100. The user can provide input data indicating the password orlogin information using the input device 212. The authenticationapplication 222 receives the sensitive input data and verifies theuser's login information based on the provided input data. During thisinput, an interloper can monitor the accelerometer signal outputted bythe accelerometer 216 to determine the sensitive input data that theuser has entered.

Other applications such as the web browser application 226 or the thirdparty applications 224 may also request that the user provide sensitiveinput data, such as a password. For example, the user may utilize athird party application 224 or the web browser application 226 to accessthe user's banking information. In such a scenario, the user may beprompted to enter sensitive input data such as a username and password.In these scenarios, an interloper can monitor the accelerometer signalto determine the sensitive input data provided by the user.

In order to reduce the likelihood that the interloper is able to obtainsensitive input data, the operating system 220, executing on theprocessor 210, can monitor the various applications to determine whetherone of the applications is requesting that the user enter sensitive userinput data. For instance, the operating system 220 may detect that theauthentication application 222 is displaying or about to display a loginscreen to the user, or that a third party application 224 or the webbrowser application 226 is operating in a “hide-text” mode. A hide-textmode can include mode that is executed when an application is requestingthat sensitive input data be provided. In the hide-text mode,predetermined symbols such as stars or dots can be shown in a text inputbox on the touch display 104 rather than displaying the actualcharacters or numbers entered by a user. When the operating system 220detects that the user has been prompted to provide sensitive input data,the operating system 220 may cause a portion of the accelerometer signalto be obscured. The portion of the accelerometer signal to be obscuredcan include certain frequency ranges of the accelerometer signal or theentire accelerometer signal. It is appreciated that while the foregoingis explained as being performed by the operating system 220, thetechniques described herein can be performed by other applications orprocesses executing on the processor 210.

Referring now to FIG. 3, an example technique 300 for obscuring anaccelerometer signal is depicted. As shown at 310, the operating system220 can determine whether a user has been prompted to provide sensitiveinput data to the mobile device 100 using the input device 212. Theforegoing may be performed until the user is prompted to enter providesensitive input data. Once the operating system 220 determines that anapplication has prompted the user to provide sensitive input data, theoperating system 220 can perform an operation to obscure a portion ofthe accelerometer signal for a period during which the user is providingthe sensitive input data, as shown at 312. For example, in someembodiments, the accelerometer signal can be obscured by: (i) switchingthe accelerometer 216 off, (ii) inserting a random noise signal into theaccelerometer signal, (iii) masking the low-order bits of theaccelerometer signal, (iv) passing the accelerometer signal through afilter, e.g., a high-pass filter, (v) actuating a vibrator of the mobiledevice 100, and/or (vi) otherwise degrading the accelerometer signal,e.g., reducing the sampling rate of the accelerometer.

The processor 210 can receive the sensitive input data from the user viathe input device 212, as shown at 314. The operating system 220 canmonitor the application requesting the sensitive input data to determinewhen the user has finished providing the sensitive input data, as shownat 316. Once the user has finished providing the sensitive input data,the operating system 220 can cease obscuring the accelerometer signal,as shown at 318. For example, when authentication is successfullyperformed on the authentication application 222, the web browserapplication 226 or third party application 224 (by receiving a user nameand password combination) the operating system 220 may cease obscuringthe accelerometer signal.

It is appreciated that the foregoing technique is provided for exampleonly. Variations of the technique are contemplated and are within thescope of the disclosure.

Referring now to FIG. 4, a functional block diagram of a processor andan accelerometer module of a mobile device according to someimplementations of the present disclosure is depicted. In the example,the accelerometer module 214 includes the accelerometer 216 and a bitmasking module 410. The accelerometer 216 outputs a raw accelerometersignal that can be modified by the bit masking module 410 to obscure theaccelerometer signal provided to the processor 210. It is appreciatedthat in this example, the accelerometer 216 may be a digitalaccelerometer that outputs a digital signal or an analog accelerometerwith an analog-to-digital converter (not shown) interposed between theaccelerometer 216 and the bit masking module 410. Upon determining thatthe user has been prompted to provide sensitive input data, theprocessor 210 can effect obscuring of a portion of the accelerometersignal by transmitting a signal, e.g., MASK_ON_SIGNAL, to the bitmasking module 410 of the accelerometer module 214 indicating that theaccelerometer signal is to be masked. The bit masking module 410 canapply a bit mask to the low-order bits of the accelerometer signal. Forinstance, the bit masking module 410 can mask the first byte with all 0s(e.g., Accelerometer Signal AND 0x00) or all 1s (e.g., AccelerometerSignal OR 0xFF). The masked accelerometer signal can then be provided tothe processor 210, which may provide the accelerometer signal to arequesting application, e.g., the GPS application 228 or a third partyapplication 224. Upon a determination that the user is no longer beingprompted to enter sensitive input data, the processor 210 can ceasetransmitting the MASK_ON_SIGNAL, and the bit masking module 410 cancease applying the bit mask to the accelerometer signal.

It is appreciated that the bit masking module 410 can be alternativelyconfigured to mask other bits, e.g., high-order bits or middle-orderbits, instead of low-order bits. It is appreciated that the foregoingexample is not intended to be limiting, and the example mobile device100 may include additional or alternative components.

Referring now to FIG. 5, a functional block diagram of a processor andan accelerometer module of a mobile device according to someimplementations of the present disclosure is depicted. In the example,the accelerometer module 214 includes the accelerometer 216 and a noisegeneration module 510. The accelerometer 216 outputs a raw accelerometersignal that can be modified by the noise generation module 510 toobscure the accelerometer signal provided to the processor 210. Theaccelerometer 216 can be a digital accelerometer that outputs a digitalsignal or an analog accelerometer that outputs an analog signal. Theaccelerometer signal can be provided to the processor 210 through thenoise generation module 510. Upon determining that the user has beenprompted to provide sensitive input data, the processor 210 can effectobscuring of a portion of the accelerometer signal by transmitting asignal, e.g., NOISE_ON_SIGNAL, to the noise generation module 510 of theaccelerometer module 214, thereby indicating that a random noise signalis to be inserted into the accelerometer signal.

The noise generation module 510 can generate the random noise signal andinsert the random noise signal into the accelerometer signal. Forinstance, the noise generation module 510 can include a random numbergenerator that generates a random number. The noise generation module510 can generate a random noise signal corresponding to the randomnumber, and then insert the random noise signal into the accelerometersignal. In some embodiments, the random noise signal is a low frequencynoise signal, such that only the low frequency portion of the signal isobscured. The frequency of the random noise signal can be selected so asto obscure the frequency range at which interlopers monitor theaccelerometer signal. It is appreciated that the random noise signal maybe inserted into the accelerometer signal in any suitable manner. Forinstance, the random noise signal may be inserted into the accelerometersignal using specific hardware, firmware, and/or software for insertingthe random noise signal into the accelerometer signal, or any othersuitable manner.

The accelerometer signal having the random noise signal inserted thereincan then be provided to the processor 210, which in turn may provide theaccelerometer signal to a requesting application, e.g., the GPSapplication 228 or a third party application 224. Upon a determinationthat the user is no longer being prompted to enter sensitive input data,the processor 210 can cease transmitting the NOISE_ON_SIGNAL and thenoise generation module 510 can cease generating the random noisesignal, thereby ceasing the obscuring of the accelerometer signal.

It is appreciated that the noise generation module 510 can bealternatively configured to generate a noise signal at otherfrequencies, thereby obscuring other portions of the accelerometersignal. It is appreciated that the foregoing example is not intended tobe limiting, and the example mobile device 100 may include additional oralternative components.

Referring now to FIG. 6, a functional block diagram of a processor andan accelerometer module of a mobile device according to someimplementations of the present disclosure is depicted. In the example,the accelerometer module 214 includes the accelerometer 216 and ahigh-pass filter 610. The accelerometer 216 outputs a raw accelerometersignal that can be modified by the high-pass filter 610 to obscure theaccelerometer signal provided to the processor 210. It is appreciatedthat in this example, the accelerometer 216 can be a digitalaccelerometer that outputs a digital signal or an analog accelerometerthat outputs an analog signal. The accelerometer signal can be providedto the processor 210 through the high-pass filter 610. Upon determiningthat the user has been prompted to provide sensitive input data, theprocessor 210 can effect obscuring of a portion of the accelerometersignal by transmitting a signal, e.g., HIGH_PASS_ON_SIGNAL, to thehigh-pass filter 610 of the accelerometer module 214 indicating that thelow frequencies of the accelerometer signal are to be filtered. Thehigh-pass filter 610, upon receiving the HIGH_PASS_ON_SIGNAL, can filterthe low-frequency portion of the accelerometer signal. The filteredaccelerometer signal can then be provided to the processor 210, whichmay provide the accelerometer signal to a requesting application, e.g.,the GPS application 228 or a third party application 224. Upon adetermination that the user is no longer being prompted to entersensitive input data, the processor 210 can stop transmitting theHIGH_PASS_ON_SIGNAL and the high-pass filter 610 can stop obscuring theaccelerometer signal.

It is appreciated that a low-pass filter or band-pass filter can be usedin lieu of or in combination with the high-pass filter. Further, theforegoing example is not intended to be limiting, and the example mobiledevice 100 may include additional or alternative components.

Referring now to FIG. 7, a functional block diagram of a processor andan accelerometer module of a mobile device according to someimplementations of the present disclosure is depicted. In the example,the accelerometer module 214 includes the accelerometer 216 and a switch710. It is appreciated that in this example, the accelerometer 216 canbe a digital accelerometer that outputs a digital signal or an analogaccelerometer that outputs an analog signal. The accelerometer 216receives a power signal from a power source, e.g., a battery of themobile device 100. The accelerometer signal can be provided to theprocessor 210 from the accelerometer 216. Upon determining that the userhas been prompted to provide sensitive input data, the processor 210 caneffect obscuring of a portion of the accelerometer signal bytransmitting a signal, e.g., ACCELEROMETER_OFF_SIGNAL, to the switch 710of the accelerometer module 214 indicating that the accelerometer is tobe turned off, i.e., the power source removed for the period duringwhich the user is providing sensitive input data. The switch 710, uponreceiving the ACCELEROMETER_OFF_SIGNAL can open, such that theaccelerometer 216 is turned off for the period during which the user isproviding the sensitive input data. Upon a determination that the useris no longer being prompted to enter sensitive input data or hasfinished providing the sensitive input data, the processor 210 can stoptransmitting the ACCELEROMETER_OFF_SIGNAL and the switch 710 can close,thereby allowing the power signal to be received by the accelerometer.

It is appreciated that the foregoing example is not intended to belimiting, and the example mobile device 100 may include additional oralternative components.

Referring now to FIG. 8, a functional block diagram of a processor, avibrator, and an accelerometer module of a mobile device is depicted. Inthe example, the mobile device 100 includes a vibrator 810 and anactuator 812. The vibrator 810 can be any suitable vibrator 810ordinarily provided in a mobile device 100. The vibrator 810 may be usedto vibrate the mobile device 100 when the mobile device 100 receives amessage or a telephone call, or otherwise provide haptic feedback to auser. The accelerometer 216 can be a digital accelerometer that outputsa digital signal or an analog accelerometer that outputs an analogsignal. The accelerometer signal can be provided to the processor 210from the accelerometer 216. Upon determining that the user has beenprompted to provide sensitive input data, the processor 210 can effectobscuring of a portion of the accelerometer signal by transmitting asignal, e.g., VIBRATOR_ON, to the actuator 812 indicating that thevibrator 810 is to be actuated, i.e., turned on. The actuator 812, uponreceiving the VIBRATOR_ON signal can actuate the vibrator 810 for theperiod during which the user is providing the sensitive input data. Insome embodiments, the vibrator 810 may be vibrated according to a randompattern, so as to further obscure the accelerometer signal, or accordingto a pattern or sequence that is effective at obscuring theaccelerometer signal. Upon a determination that the user is no longerbeing prompted to enter sensitive input data or has finished providingthe sensitive input data, the processor 210 can stop transmitting theVIBRATOR_ON signal and the actuator 812 stops actuating the vibrator810. It is appreciated that the foregoing example is not intended to belimiting, and the example mobile device 100 may include additional oralternative components.

As discussed above, various other techniques may be implemented forobscuring the accelerometer signal. For instance, the processor 210 maybe configured to adjust the power supply rails to a comparator circuit(not shown) of an analog-to-digital converter (not shown) of theaccelerometer module 214 for the period during which the user isproviding the sensitive input data. Further, the processor 210 may beconfigured to shunt the accelerometer signal to a ground for the periodduring which the user is providing the sensitive input data.Alternatively, the accelerometer signal may be sampled at a lower ratefor the period during which the user is providing the sensitive inputdata.

Example embodiments are provided so that this disclosure will bethorough, and will fully convey the scope to those who are skilled inthe art. Numerous specific details are set forth such as examples ofspecific components, devices, and methods, to provide a thoroughunderstanding of embodiments of the present disclosure. It will beapparent to those skilled in the art that specific details need not beemployed, that example embodiments may be embodied in many differentforms and that neither should be construed to limit the scope of thedisclosure. In some example embodiments, well-known procedures,well-known device structures, and well-known technologies are notdescribed in detail.

The terminology used herein is for the purpose of describing particularexample embodiments only and is not intended to be limiting. As usedherein, the singular forms “a,” “an,” and “the” may be intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. The term “and/or” includes any and all combinations of one ormore of the associated listed items. The terms “comprises,”“comprising,” “including,” and “having,” are inclusive and thereforespecify the presence of stated features, integers, steps, operations,elements, and/or components, but do not preclude the presence oraddition of one or more other features, integers, steps, operations,elements, components, and/or groups thereof. The method steps,processes, and operations described herein are not to be construed asnecessarily requiring their performance in the particular orderdiscussed or illustrated, unless specifically identified as an order ofperformance. It is also to be understood that additional or alternativesteps may be employed.

Although the terms first, second, third, etc. may be used herein todescribe various elements, components, regions, layers and/or sections,these elements, components, regions, layers and/or sections should notbe limited by these terms. These terms may be only used to distinguishone element, component, region, layer or section from another region,layer or section. Terms such as “first,” “second,” and other numericalterms when used herein do not imply a sequence or order unless clearlyindicated by the context. Thus, a first element, component, region,layer or section discussed below could be termed a second element,component, region, layer or section without departing from the teachingsof the example embodiments.

As used herein, the term module may refer to, be part of, or include anApplication Specific Integrated Circuit (ASIC); an electronic circuit; acombinational logic circuit; a field programmable gate array (FPGA); aprocessor (shared, dedicated, or group) that executes code, or a processexecuted by a distributed network of processors and storage in networkedclusters or datacenters; other suitable components that provide thedescribed functionality; or a combination of some or all of the above,such as in a system-on-chip. The term module may include memory (shared,dedicated, or group) that stores code executed by the one or moreprocessors.

The term code, as used above, may include software, firmware, byte-codeand/or microcode, and may refer to programs, routines, functions,classes, and/or objects. The term shared, as used above, means that someor all code from multiple modules may be executed using a single(shared) processor. In addition, some or all code from multiple modulesmay be stored by a single (shared) memory. The term group, as usedabove, means that some or all code from a single module may be executedusing a group of processors. In addition, some or all code from a singlemodule may be stored using a group of memories.

The techniques described herein may be implemented by one or morecomputer programs executed by one or more processors. The computerprograms include processor-executable instructions that are stored on anon-transitory tangible computer readable medium. The computer programsmay also include stored data. Non-limiting examples of thenon-transitory tangible computer readable medium are nonvolatile memory,magnetic storage, and optical storage.

Some portions of the above description present the techniques describedherein in terms of algorithms and symbolic representations of operationson information. These algorithmic descriptions and representations arethe means used by those skilled in the data processing arts to mosteffectively convey the substance of their work to others skilled in theart. These operations, while described functionally or logically, areunderstood to be implemented by computer programs. Furthermore, it hasalso proven convenient at times to refer to these arrangements ofoperations as modules or by functional names, without loss ofgenerality.

Unless specifically stated otherwise as apparent from the abovediscussion, it is appreciated that throughout the description,discussions utilizing terms such as “processing” or “computing” or“calculating” or “determining” or “displaying” or the like, refer to theaction and processes of a computer system, or similar electroniccomputing device, that manipulates and transforms data represented asphysical (electronic) quantities within the computer system memories orregisters or other such information storage, transmission or displaydevices.

Certain aspects of the described techniques include process steps andinstructions described herein in the form of an algorithm. It should benoted that the described process steps and instructions could beembodied in software, firmware or hardware, and when embodied insoftware, could be downloaded to reside on and be operated fromdifferent platforms used by real time network operating systems.

The present disclosure also relates to an apparatus for performing theoperations herein. This apparatus may be specially constructed for therequired purposes, or it may comprise a general-purpose computerselectively activated or reconfigured by a computer program stored on acomputer readable medium that can be accessed by the computer. Such acomputer program may be stored in a tangible computer readable storagemedium, such as, but is not limited to, any type of disk includingfloppy disks, optical disks, CD-ROMs, magnetic-optical disks, read-onlymemories (ROMs), random access memories (RAMs), EPROMs, EEPROMs,magnetic or optical cards, application specific integrated circuits(ASICs), or any type of media suitable for storing electronicinstructions, and each coupled to a computer system bus. Furthermore,the computers referred to in the specification may include a singleprocessor or may be architectures employing multiple processor designsfor increased computing capability.

The algorithms and operations presented herein are not inherentlyrelated to any particular computer or other apparatus. Variousgeneral-purpose systems may also be used with programs in accordancewith the teachings herein, or it may prove convenient to construct morespecialized apparatuses to perform the required method steps. Therequired structure for a variety of these systems will be apparent tothose of skill in the art, along with equivalent variations. Inaddition, the present disclosure is not described with reference to anyparticular programming language. It is appreciated that a variety ofprogramming languages may be used to implement the teachings of thepresent disclosure as described herein, and any references to specificlanguages are provided for disclosure of enablement and best mode of thepresent invention.

The present disclosure is well suited to a wide variety of computernetwork systems over numerous topologies. Within this field, theconfiguration and management of large networks comprise storage devicesand computers that are communicatively coupled to dissimilar computersand storage devices over a network, such as the Internet.

The foregoing description of the embodiments has been provided forpurposes of illustration and description. It is not intended to beexhaustive or to limit the disclosure. Individual elements or featuresof a particular embodiment are generally not limited to that particularembodiment, but, where applicable, are interchangeable and can be usedin a selected embodiment, even if not specifically shown or described.The same may also be varied in many ways. Such variations are not to beregarded as a departure from the disclosure, and all such modificationsare intended to be included within the scope of the disclosure.

What is claimed is:
 1. A computer-implemented method comprising:determining, at a computing device including at least one processor andan accelerometer, that a user has been prompted to provide sensitiveinput data to the computing device; when the user has been prompted toprovide sensitive input data to the computing device, beginning toobscure a portion of an accelerometer signal output from theaccelerometer to obtain an obscured accelerometer signal; and receivingthe sensitive input data from the user while the portion of theaccelerometer signal is obscured.
 2. The method of claim 1 furthercomprising: determining that the user has finished entering thesensitive input data; and ceasing to obscure the portion of theaccelerometer signal when the user has finished entering the sensitiveinput data.
 3. The method of claim 1, further comprising receiving, atthe at least one processor, the obscured accelerometer signal.
 4. Themethod of claim 1, wherein obscuring the portion of the accelerometersignal output from the accelerometer includes turning off theaccelerometer, and wherein the obscured accelerometer signal comprisesno signal.
 5. The method of claim 1, wherein obscuring the portion ofthe accelerometer signal output from the accelerometer includesinserting a noise signal into the accelerometer signal to obtain theobscured accelerometer signal.
 6. The method of claim 5, wherein thenoise signal is based on one or more random numbers generated by arandom number generator.
 7. The method of claim 5, wherein the noisesignal is a low-frequency range signal, and wherein the portion of theaccelerometer signal that is obscured is a low-frequency range.
 8. Themethod of claim 1, wherein obscuring the portion of the accelerometersignal output from the accelerometer includes actuating a vibrator ofthe mobile device.
 9. The method of claim 1, wherein obscuring theportion of the accelerometer signal output from the accelerometerincludes filtering the accelerometer signal.
 10. The method of claim 9,wherein filtering the accelerometer signal includes applying a bit maskto the accelerometer signal.
 11. A computing device comprising: an inputdevice configured to receive input data from a user; an accelerometermodule including an accelerometer; and a processing device incommunication with the input device and the accelerometer module andconfigured to determine whether the user has been prompted to providesensitive input data to the computing device using the input device,and, when the user has been prompted to provide the sensitive input datato the computing device, to begin obscuring of a portion of anaccelerometer signal output by the accelerometer to obtain an obscuredaccelerometer signal.
 12. The mobile device of claim 11, wherein theprocessing device is further configured to determine that the user hasfinished entering the sensitive input data and to cease to obscure theportion of the accelerometer signal upon determining that the user hasfinished entering the sensitive input data.
 13. The mobile device ofclaim 11, wherein the accelerometer module further includes a bitmasking module that receives the accelerometer signal from theaccelerometer and masks one or more low-order bits of the rawaccelerometer signal to obtain the obscured accelerometer signal. 14.The mobile device of claim 13, wherein the accelerometer is a digitalaccelerometer and the accelerometer signal is a digital signal having apredetermined amount of bits, including the low-order bits.
 15. Themobile device of claim 11, wherein the accelerometer module furtherincludes a noise generation module configured to insert a noise signalinto the accelerometer signal to obtain the obscured accelerometersignal.
 16. The mobile device of claim 15, wherein the noise signal is alow frequency range signal, and wherein the portion of the accelerometersignal that is obscured is a low-frequency range.
 17. The mobile deviceof claim 11, wherein the accelerometer module further includes a switchthat selectively turns off the accelerometer to obscure theaccelerometer signal, wherein the obscured accelerometer signalcomprises no signal.
 18. The mobile device of claim 11, wherein theprocessing device includes one or more processors.
 19. Acomputer-implemented method comprising: determining, at a processingdevice of a computing device, that a user has been prompted to providesensitive input data to the computing device; when the user has beenprompted to provide sensitive input data to the computing device,beginning to obscure a portion of an accelerometer signal output from anaccelerometer of the computing device to obtain an obscuredaccelerometer signal; receiving, at the processing device, the obscuredaccelerometer signal; receiving the sensitive input data from the userwhile the portion of the accelerometer signal is obscured; determining,at the processing device, that the user has finished entering thesensitive input data; and ceasing to obscure the portion of theaccelerometer signal when the user has finished entering the sensitiveinput data.
 20. The method of claim 19, wherein the processing deviceincludes one or more processors.